Cooling system devices that dissipate heat generated by burning of fuel compulsorily exist in internal combustion engines. All the engines that use gas, kerosene, gasoline, and diesel as fuel belong to the internal combustion engines. For example, the cooling system of an automobile uses coolant solution composed mainly of glycols, and excessive overheating of engine by leakage and depletion of coolant by any means can shorten durability of the engine and cause metallic cracks on the engine parts.
Cracks, openings, and microscopic holes on a radiator, cylinder block, cylinder head, and cylinder head gasket participating in cooling of internal combustion engines, cause waste of unnecessary resources and economical defrayment of consumers when no other methods are available but replacing the relevant parts as the sole solution.
There have been efforts to repair cracks of internal combustion engines without disassembling and replacing damaged devices, and several products are commercialized and marketed. One such representative example of using sodium silicate, main ingredient of majority of currently marketed crack repairing products, can be found in U.S. Pat. No. 4,708,195 (1987). Sealing formulation of 95.8% sodium silicate, 4.1% water, 0.16% cupric sulfate pentahydrate, and 0.005% arabic gum has been disclosed. In another U.S. Pat. No. 4,765,629 (1988) described a sealing system composed of a liquid carrier and solid particles, a liquid carrier composed of water and sodium silicate, and solid particles selected from silver solder flakes, lead solder flakes and pure ground pepper, and solidifying at 150° F. in the crack. In still another application, U.S. Pat. No. 4,973,360 (1990) expanded on the kinds of silicates in addition to sodium or potassium silicate already in use, and disclosed a sealant solution composed of 25% water, 25% ethylene glycol, and 50% aqueous solution composed of compounds selected from silicates of lithium, ammonium, rubidium, cesium, and germanium, and oxides of sodium oxide with aluminum oxide, calcium oxide or magnesium oxide. Synthetic polymer polyacrylic acid was first described in U.S. Pat. No. 6,767,395 (2004). In that application, a liquid aluminum stop-leak formulation comprising water, polyacrylic acid, cellulose fibers of 0.075˜0.3 mm, polyester fiber of 0.3 mm, aluminum particles of about 32 and other components are disclosed. In U.S. Pat. No. 6,840,990, a sealing composition incorporating sodium nitrate or azoles as corrosion inhibitors is described.